Good to hear you worked out the sample rate.
Yes, what ever they are doing it does sound pretty darn good - better than Spotify IMO.
Every time the pop up comes up asking me to rate the product, I always mention that bit perfect exclusive mode and that maybe if they had that I would not need Qobuz, lol
If you google AmazonHD exclusive mode you will see you are not alone - there’s even some place you can go to let amazon know you are pissed about it - I’m not bothered enough to do that but… And from what I’ve seen they dance around it in the terms and conditions.
Anyway it looks like you are able to enjoy your music a little more now - and that’s what really matters!